About a year ago I purchased an RV6A but I am running into high oil temps on climb out and cruise. I have a James aircraft cowling with an IO-360 engine (200hp). On climb out I generally climb out I generally stop at 2000 feet with an oil temp of 215 degrees and let some airflow into the engine. I continue my climb at 500fpm and generally by the time I reach my cruising altitude of 5500-6500 feet with a power setting of 22' MP and 2200 RPM the oil temps are 230-240 degrees. Running LOP my oil temps will drop to about 215 degrees. The OAT during these flight was 66-75 degrees. I have attached some pictures of my oil cooling set up and gain some input from the masses. Thank you for any input you can provide.
Van's Air Force
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RV6A High Oil Temps
- Thread starter DavidSLewis
- Start date
Carl Froehlich
Well Known Member
What oil cooler are you using?
Carl
Carl
Dad's RV-10
Well Known Member
Images rotated:
I'm not sure, I didn't see anything in the logbooks so I'll get the brand when I get back out to the hanger. I know it has 9 rows but that is all I know right now
D-Dubya
Well Known Member
I believe the angle valve IO-360 squirts oil on the underside of the pistons and utilizes this for additional engine cooling. So the oil has to absorb more heat than the parallel valve 180 HP version of the same engine. My guess is that you'll need a larger oil cooler. It appears from the photos that you have a plenum with a 4" hose going to the cooler and a reasonably nice inlet to the oil cooler, so all of that looks good.
You might want to do a search on here to see what size people are using with that engine, but I seem to remember that one of the 13 row coolers are common. I'm sure someone will correct me if I'm wrong. I'm going off my somewhat sketchy memory...
You might want to do a search on here to see what size people are using with that engine, but I seem to remember that one of the 13 row coolers are common. I'm sure someone will correct me if I'm wrong. I'm going off my somewhat sketchy memory...
hgerhardt
Well Known Member
I used to think so too until I characterized my very similar installation. Turns out 4" SCAT has a huge deltaP loss in this situation. Have a look at this thread: https://vansairforce.net/community/showthread.php?t=188113
Also, I agree that cooler is too small for an angle-valve, especially when used in a ducted situation as this.
Thoughts...
1. Change out the SCAT for SCEET.
2. A larger bellmouth on the inlet to the duct (share a picture of that side of the baffle, under the plenum cover), will help keep the pressure up and not restrict the airflow.
3. The diffuser (black thing in the pics) transition from the duct to the rectangular face of the oil cooler should be as long as possible -- I think the sweet spot for optimum pressure recovery and non-turbulent flow is around 17° (or was it 19°), no bends or other transitions for the air to get tripped up or fall off.
4. The OP's oil cooler is a two pass type (similar to SW 8432). Not your included-in-the-kit "9-row"...
As an aside - Oil cooler "rows" is almost meaningless as far as efficiency is concerned, and I wish we could stop using that as a descriptor for oil coolers.
With a 4" duct, you should be "ok" with a REAL/GENUINE/NOT-A-CLONE of the Stewart Warner/Southwind/Meggitt/Troy "8406R", the "10599R" is more than adequate, and the "10610R" is overkill IMHO...
Cheers!
B
1. Change out the SCAT for SCEET.
2. A larger bellmouth on the inlet to the duct (share a picture of that side of the baffle, under the plenum cover), will help keep the pressure up and not restrict the airflow.
3. The diffuser (black thing in the pics) transition from the duct to the rectangular face of the oil cooler should be as long as possible -- I think the sweet spot for optimum pressure recovery and non-turbulent flow is around 17° (or was it 19°), no bends or other transitions for the air to get tripped up or fall off.
4. The OP's oil cooler is a two pass type (similar to SW 8432). Not your included-in-the-kit "9-row"...
As an aside - Oil cooler "rows" is almost meaningless as far as efficiency is concerned, and I wish we could stop using that as a descriptor for oil coolers.
With a 4" duct, you should be "ok" with a REAL/GENUINE/NOT-A-CLONE of the Stewart Warner/Southwind/Meggitt/Troy "8406R", the "10599R" is more than adequate, and the "10610R" is overkill IMHO...
Cheers!
B
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